Responding to a 6:40 p.m. accident call, police officers determined that the victim was riding his Yamaha dirt bike north on Route 137 when he was struck from behind by a pipe buggy operated by Samuel Santos, 43, of Ainaloa subdivision. Reis was thrown from his motorcycle and sustained head injuries. He was not wearing a helmet.

The victim was taken to the Hilo Medical Center, where he was pronounced dead at 9:25 p.m. A 56-year-old female passenger in the pipe buggy was also taken to the hospital, where she was treated and later released. Santos was not injured in the accident.

Traffic Enforcement Unit officers are continuing the investigation to determine if speed or alcohol was involved in the accident. They have ordered an autopsy to determine the exact cause of death and have initiated a standard negligent homicide investigation.

Reis’s death was the ninth traffic fatality so far this year, compared to 15 at the same time last year.